A series of substituted oxazole compounds having an alpha keto side chain at the 2 position and an aromatic, heteroaromatic or heterocycle substituent at the 5 position are disclosed. These compounds exhibit inhibition of fatty acid amid hydrolase and arc useful for treatment of malconditions involving that enzyme.

PRIORITY CLAIM TO RELATED APPLICATIONS

This application is a national stage application under 35 U.S.C. §371 of PCT/US2008/006913, filed May 30, 2008, and published as WO 2008/150492 A1 on Dec. 11, 2008, which claims priority to U.S. Application No. 60/932,494, filed May 31, 2007, which applications and publication are incorporated herein by reference and made a part hereof in their entirety, and the benefit of priority is claimed thereto.

Claims:

What is claimed is:

1. A compound having the following structure: wherein Ar is a phenyl or pyridyl having a carbon as its point of attachment to the oxazole; R1 is independently selected from the group consisting of hydrogen, —(C1-C6 alkyl), —(C3-C6 alkyl), —CF3, —CN, —C(O)C1-C4 alkyl optionally substituted with one, two, or three fluoro substituents, —CO2(C1-C4 alkyl), —CO2H, —C(O)N(Ra)Rb, —OH, —O(C1-C6 alkyl), halo, —NO2, —NRaRb, —N(Ra)C(O)Rb, —N(Ra)SO2Rb, —SO2N(Ra)Rb, —SRa, —S(O)Ra, and —SO2Ra; where Ra and Rb are each independently selected from the group consisting of —H, —(C1-C6 alkyl), and —(C3-C6 cycloalkyl); and R2 is independently selected from the group consisting of hydrogen, —(C1-C6 alkyl), —(C3-C6 alkyl), —CF3, —CN, —C(O)C1-C4 alkyl optionally substituted with one, two, or three fluoro substituents, —CO2(C1-C4 alkyl), —CO2H, —C(O)N(Rc)Rd, —OH, —O(C1-C6 alkyl), -halo, —NO2, —NRcRd, —N(Rc)C(O)Rd, —N(Rc)SO2Rd, —SO2N(Rc)Rd, —SRC, —S(O)RC, —SO2Rc; where Rc and Rd are each independently selected from the group consisting of —H, —(C1-C6 alkyl), and —(C3-C6 cycloalkyl); and Ar1 is selected from the group consisting of: X is selected from the group of diradicals consisting of —CH2—, —O—, —S—, —S(O)—, —S(O)2—, —NR5—, —CH(OH)—, and —C(O)NH—; and R3 is selected from the group consisting of —NHBOC, —Cl, —Br, —I, —NH2, —NO2, —O(C1-C6 alkyl), —S(C1-C6 alkyl), —S(O)(C1-C6 alkyl), —S(O)2(C1-C6 alkyl), —CF3, —COOH, and —CO2(C1-C6 alkyl); R4 is selected from the group consisting of —H, —NHBOC, —Cl, —Br, —I, —NH2, —NO2, —O(C1-C6 alkyl), —S(C1-C6 alkyl), —S(O)(C1-C6 alkyl), —S(O)2(C1-C6 alkyl), —CF3, —COOH, and —CO2(C1-C6 alkyl); and R5 is selected from the group consisting —H, and —(C1-C6 alkyl); and Z is selected from the group of diradicals consisting of —O—, —S—, and —NR5—; and m is an integer between 0 and 6; and n is an integer between 0 and 6; with the following provisos: if m is 0, then n cannot be 0; and if X is —CH2—, then Ar1 cannot be phenyl; or a pharmaceutically acceptable salt thereof.

2. A compound according to claim 1, wherein Ar is selected from the group consisting of the following

3. A compound according to claim 1, wherein R1 is selected from the group consisting of —CH3, —CF3, —CN, —C(O)CF3, —CO2CH3, —CO2H, —C(O)NH2, —OH, —OCH3, —F, —NO2, —NH2, and —SO2NH2.

4. A compound according to claim 1, wherein R2 is —H.

5. A compound according to claim 2, wherein R1 is selected from the group consisting of —CH3, —CF3, —CN, —C(O)CF3, —CO2CH3, —CO2H, —C(O)NH2, —OH, —OCH3, —F, —NO2, —NH2, and —SO2NH2.

6. A compound according to claim 2, wherein R2 is —H.

7. A compound according to claim 2, wherein R1 is selected from the group consisting of —CH3, —CF3, —CN, —C(O)CF3, —CO2CH3, —CO2H, —C(O)NH2, —OH, —OCH3, —F, —NO2, —NH2, and —SO2NH2.

8. A compound according to claim 2, wherein R2 is —H.

9. A compound according to claim 7, wherein R2 is —H.

10. A compound according to claim 1, having the following structure:

11. A compound according to claim 10, having any of the following structures, or a pharmaceutically acceptable salt thereof:

12. A pharmaceutical composition comprising a compound of claim 1 and a pharmaceutically acceptable carrier.

13. A pharmaceutical combination comprising a compound of claim 1 in combination with another FAAH modulator or another biologically active agent.

14. A pharmaceutical combination of claim 13 wherein the active ingredient is an opiod, an NSAID, gabapentin, pregabalin, tramadol, acetaminophen or aspirin.

Description:

STATEMENT OF GOVERNMENT SUPPORT

A portion of the work described herein was supported by grant number DA 15648 from the National Institutes of Health. The United States Government has certain rights in this invention.

FIELD OF THE INVENTION

The present invention related to certain oxazole compounds, pharmaceutical compositions containing them, and methods of using them for the treatment of disease states, disorders, and conditions mediated by fatty acid amide hydrolase (FAAH) activity.

The present invention concerns the synthesis and evaluation of a systematic series of α-keto oxazole inhibitors having variations at the C2 acyl side chain along with results of the proteome-wide selectivity screening of the candidate inhibitors. The screening protocol is described by Leung, D.; Hardouin, C.; et al. Nature Biotech. 2003, 21, 687-691.

SUMMARY OF THE INVENTION

The novel 2-keto-oxazole derivatives of the invention have FAAH-modulating activity. A series of derivatives was prepared and evaluated for FAAH inhibitory potency as well as FAAH selectivity versus competitive serine proteases (e.g., TGH, KIAA1363). Aryl substitutions along the acyl side chain resulted in effective inhibitors. A large series of phenyl substituents proved to be effective inhibitors with hydrophobic or electron-withdrawing meta substituents generally enhancing binding affinity to the greatest extent, for example, compound 5hh (aryl=3-Cl—Ph, Ki=900 pM) displayed extremely potent activity. A systematic series of heteroatoms (O, NMe, S) and electron-withdrawing groups (SO, SO2) positioned within the acyl side chain was investigated. The most tolerant position (position 6) along the acyl side chain provided effective inhibitors (see compound 12p, X=S, Ki=3 nM). A series of amides within the linking chain and hydroxyl substitutions on the chain were also explored. The activity of the compounds having amide placement at various positions along the side chain varied in potency. Hydroxyl substitution at positions 2 and 6 provided highly effective inhibitors (13a, 2-position OH, Ki=8 nM). Just as importantly, proteome-wide selectivity screening of the candidate inhibitors showed extraordinary selectivity for FAAH over all other serine hydrolases and proteases.

More particularly, in one general aspect, the invention relates to compounds of the following Formula (I), represented by following structure:

In Formula I, Ar is a 5- or 6-membered aryl or heteroaryl ring having a carbon as its point of attachment to the oxazole; R1 is independently selected from the group consisting of —(C1-C6 alkyl), —(C3-C6 alkyl), —CF3, —CN, —C(O)C1-C4 alkyl optionally substituted with one, two, or three fluoro substituents, —CO2(C1-C4 alkyl), —CO2H, —C(O)N(Ra)Rb, —OH, —O(C1-C6 alkyl), halo, —NO2, —NRaRb, —N(RaC(O)Rb, —N(Ra)SO2Rb, —SO2N(Ra)Rb, —SRa, —S(O)Ra, —SO2Ra; where Ra and Rb are each independently selected from the group consisting of —H, —(C1-C6 alkyl), and —(C3-C6 cycloalkyl); and R2 is independently selected from the group consisting of —(C1-C6 alkyl), —(C3-C6 alkyl), —CF3, —CN, —C(O)C1-C4 alkyl optionally substituted with one, two, or three fluoro substituents, —CO2(C1-C4 alkyl), —CO2H, —C(O)N(Rc)Rd, —OH, —O(C1-C6 alkyl), -halo, —NO2, —NRcRd, —N(Rc)C(O)Rd, —N(Rc)SO2Rd, —SO2N(Rc)Rd, —SRc, —S(O)Rc, —SO2Rc; where Rc and Rd are each independently selected from the group consisting of —H, —(C1-C6 alkyl), or —(C3-C6 cycloalkyl); and Ar1 selected from the group consisting of the following radicals:

X is selected from the group of diradicals consisting of —CH2—, —O—, —S—, —S(O)—, —S(O)2—, —NR5—, —C≡C—, —CH(OH)—, —C(O)NH—; and R3 and R4 are independently selected from the group consisting —H, —NHBOC, —F, —Cl, —Br, —I, —NH2, —NO2, —O(C1-C6 alkyl), —S(C1-C6 alkyl), —S(O)(C1-C6 alkyl), —S(O)2(C1-C6 alkyl), —CF3, —COOH, —CO2(C1-C6 alkyl), —(C1-C6 alkyl); R5 is selected from the group consisting of —H, and —(C1-C6 alkyl); and Z is selected from the group of diradicals consisting of —O—, —S—, and —NR5—; and

m is an integer between 0 and 6; and n is an integer between 0 and 6. However, the following provisos apply: if m is 0, then n cannot be 0; and if X is —CH2—, then Ar1 cannot be phenyl. In a preferred embodiment, Ar is selected from the group consisting of phenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrimidinedione, pyrazinyl, thiophenyl, furanyl, imidazolyl, oxazolyl, triazolyl and tetrazolyl. In other preferred embodiments, Ar is selected from the following group:

where R6═(C1-C6 alkyl).

In yet other embodiments, R1 is selected from the group consisting of —CH3, —CF3, —CN, —C(O)CF3, —CO2CH3, —CO2H, —C(O)NH2, —OH, —OCH3, —F, —NO2, —NH2, and —SO2NH2. Preferably, R2 is —H.

Another aspect of the invention is directed to a process for inhibiting the catalytic activity of fatty acid amide hydrolase. The process comprises the step of contacting the fatty acid amide hydrolase with a solution having an inhibitory concentration of a compound of Formula I.

In preferred embodiments, the compound of Formula (I) is a compound specifically described or exemplified in the detailed description below.

In a further general aspect, the invention relates to pharmaceutical compositions each comprising: (a) an effective amount of an agent selected from compounds of Formula (I) and pharmaceutically acceptable salts, pharmaceutically acceptable prodrugs, and pharmaceutically active metabolites thereof; and (b) a pharmaceutically acceptable excipient.

In another general aspect, the invention relates to pharmaceutical combinations of a compound of Formula I and another bioactive agent such as another FAAH inhibitor, as well as NSAIDS, Cox inhibitors and the like as described in detail in the following section.

In another general aspect, the invention relates to prodrugs and active metabolites of a compound of Formula I.

In another general aspect, the invention is directed to a method of treating a subject suffering from or diagnosed with a disease, disorder, or medical condition mediated by FAAH activity, comprising administering to the subject in need of such treatment an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt, pharmaceutically acceptable prodrug, or pharmaceutically active metabolite of such compound.

Additional embodiments, features, and advantages of the invention will be apparent from the appended claims, which are incorporated into this summary by reference, as well as from the following detailed description.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates both anandamide (1a) and oleamide (1b) undergoing hydrolysis by fatty acid amide hydrolase (FAAH) to their respective carboxylic acids. Both have emerged as prototypical members of the class of bioactive lipid amides that serve as chemical messengers. The pharmacological actions of anandamide (1a) and oleamide (1b) are terminated by FAAH. The enzyme fatty acid amide hydrolase converts Oleamide (1b) to Oleic acid (1d), and Anandamide (1a) to Arachidonic acid (1c).

FIG. 2 shows the structures of URB-597 and OL-135 along with their respective activities. URB-597 is from one class comprising the aryl carbamates that acylate an active site catalytic serine and which were shown to exhibit anxiolytic activity and induce analgesia. OL-135 is an example of a ketoheterocycle-based inhibitor.

FIG. 3 illustrates how the majority of the candidate inhibitors were prepared.

FIG. 4 illustrates the methods used in the synthesis of the inhibitors that were not prepared by either Method A or B.

FIG. 5 illustrates a collection of tables showing a systematic series of aryl replacements and phenyl substitutions for the terminal phenyl group of OL-135 (2b).

FIG. 6 illustrates two tables where the linker chain contains an alkynyl group connecting the methylene portion to the aryl ring.

FIG. 7 illustrates a series of tables showing the effects of substitution along the side chain.

FIG. 8 illustrates a table showing a series of amides within the linking chain and hydroxyl substitutions on the chain was also explored.

FIG. 9 illustrates is a table showing several additional side chain modifications that were examined and represent intermediates or byproducts derived from the synthesis of the preceding candidate inhibitors.

FIG. 10 illustrates a short table listing the differing Ki's between human FAAH and rat FAAH for some of the more potent compounds.

FIG. 11 illustrates is a table showing the Ki with FAAH and the other columns are IC50's with FAAH, KIAA1363 and TGH.

DETAILED DESCRIPTION OF INVENTION AND ITS EMBODIMENTS

The present invention concerns substituted oxazole compounds having an alpha keto side chain at the 2 position of oxazole and an aryl or heteroaryl substituent at the 5 position of the oxazole. A series of aryl variations along the alpha keto side chain provided effective inhibitors (e.g., 5c, aryl=1-napthyl, Ki=2.6 nM) and an extensive series of phenyl substituents were incorporated to provide effective inhibitors with hydrophobic or electron-withdrawing meta substituents most significantly enhancing binding affinity. For example compound 5hh (aryl=3-Cl-Ph, Ki=900 pM) described below had extreme potency. Also, a series of heteroatom substitutions along the alpha keto side chain (O, NMe, S) and electron-withdrawing groups (SO, SO2) were explored. It was discovered that these substitutions affected potency such that substitution β to the electrophilic carbonyl lowers potency. The most tolerant position (position 6 along the chain) provided effective inhibitors (12p, X═S, Ki=3 nM). A series of amides within the linking chain and hydroxyl substitutions on the chain were also explored. Amide placement within the side chain led to variation in inhibitory potency whereas hydroxyl substitution at positions 2 and 6 provided effective inhibitors (13d, 2-position OH, Ki=8 nM). Proteomic-wide screening of selected candidate inhibitors revealed that these new inhibitors are exquisitely selective for FAAH over all other mammalian serine proteases.

The invention may be more fully appreciated by reference to the following description, including the following glossary of terms and the concluding examples. For the sake of brevity, the disclosures of the publications cited in this specification are herein incorporated by reference.

As used herein, the terms “including”, “containing” and “comprising” are used herein in their open, non-limiting sense.

Unless otherwise indicated by the text of this application, the use of the single articles of speech, “a”, “an” and “the” include both the singular form and the plural form of the nouns with which they are associated. For example the term “a compound of Formula I” includes each single compound of Formula I, multiple compounds of Formula I and the group of compounds delineated by Formula I such that this term encompasses the phrases “compounds delineated by Formula I and “an individual compound delineated by Formula I.”

The term “alkyl” refers to a straight- or branched-chain alkyl group having from 1 to 12 carbon atoms in the chain. Exemplary alkyl groups include methyl (Me, which also may be structurally depicted by /), ethyl (Et), n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl (tBu), pentyl, isopentyl, tert-pentyl, hexyl, isohexyl, and the like.

The term “aryl” refers to a monocyclic, fused bicyclic, or fused polycyclic, aromatic carbocycle (ring structure having ring atoms that are all carbon) having from 3 to 12 ring atoms per carbocycle. (Carbon atoms in aryl groups are sp2 hybridized.) Illustrative examples of aryl groups include phenyl, naphthyl, anthracenyl, phenanthrenyl, and the like.

The term “heteroaryl” refers to a monocyclic, fused bicyclic, or fused polycyclic aromatic heterocycle (ring structure having ring atoms selected from carbon atoms as well as nitrogen, oxygen, and sulfur heteroatoms) having from 3 to 12 ring atoms per heterocycle. Illustrative examples of heteroaryl groups include the following moieties:

and the like.

The term “cycloalkyl” refers to a saturated or partially saturated, monocyclic, fused polycyclic, or spiro polycyclic, carbocycle having from 3 to 12 ring atoms per carbocycle. Illustrative examples of cycloalkyl groups include the following moieties:

and the like.

The term “halogen” represents chlorine, fluorine, bromine or iodine. The term “halo” represents chloro, fluoro, bromo or iodo.

The term “substituted” means that the specified group or moiety bears one or more substituents. The term “unsubstituted” means that the specified group bears no substituents. The term “optionally substituted” means that the specified group is unsubstituted or substituted by one or more substituents. Where the term “substituted” is used to describe a structural system, the substitution is meant to occur at any valency-allowed position on the system.

Any formula given herein is intended to represent compounds having structures depicted by the structural formula as well as certain variations or forms. In particular, compounds of any formula given herein may have asymmetric centers and therefore exist in different enantiomeric forms. All optical isomers and stereoisomers of the compounds of the general formula, and mixtures thereof, are considered within the scope of the formula. Thus, any formula given herein is intended to represent a racemate, one or more enantiomeric forms, one or more diastereomeric forms, one or more atropisomeric forms, and mixtures thereof.

Furthermore, certain structures may exist as geometric isomers (i.e., cis and trans isomers), as tautomers, or as atropisomers. Additionally, any formula given herein is intended to represent hydrates, solvates, and polymorphs of such compounds, and mixtures thereof.

Any formula given herein is also intended to represent unlabeled forms as well as isotopically labeled forms of the compounds. Isotopically labeled compounds have structures depicted by the formulas given herein except that one or more atoms are replaced by an atom having a selected atomic mass or mass number. Examples of isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, sulfur, phosphorous, fluorine, and chlorine, such as 2H, 3H, 11C, 13C, 14C, 15N, 18O, 17O, 31P, 32P, 35S, 18F, 36Cl, 125I, respectively. Various isotopically labeled compounds of the present invention, for example those into which radioactive isotopes such as 3H, 11C, and 14C are incorporated. Such isotopically labeled compounds are useful in metabolic studies (preferably with 14C), reaction kinetic studies (with, for example 2H or 3H), detection or imaging techniques [such as positron emission tomography (PET) or single-photon emission computed tomography (SPECT)] including drug or substrate tissue distribution assays, or in radioactive treatment of patients. In particular, an 18F or 11C labeled compound may be particularly preferred for PET or SPECT studies. Further, substitution with heavier isotopes such as deuterium (i.e., 2H) may afford certain therapeutic advantages resulting from greater metabolic stability, for example increased in vivo half-life or reduced dosage requirements. Isotopically labeled compounds of this invention and prodrugs thereof can generally be prepared by carrying out the procedures disclosed in the schemes or in the examples and preparations described below by substituting a readily available isotopically labeled reagent for a non-isotopically labeled reagent.

When referring to any formula given herein, the selection of a particular moiety from a list of possible species for a specified variable is not intended to define the moiety for the variable appearing elsewhere. In other words, where a variable appears more than once, the choice of the species from a specified list is independent of the choice of the species for the same variable elsewhere in the formula.

In preferred embodiments of the invention, Ar is selected from the group consisting of phenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrimidine-dione, pyrazinyl, thiophenyl, furanyl, imidazolyl, oxazolyl, and tetrazolyl.

The invention includes also pharmaceutically acceptable salts of the compounds represented by Formula (I), such as of those described above. Pharmaceutically acceptable salts of the specific compounds exemplified are especially preferred.

If the compound of Formula (I) is an acid, such as a carboxylic acid or sulfonic acid, the desired pharmaceutically acceptable salt may be prepared by any suitable method, for example, treatment of the free acid with an inorganic or organic base, such as an amine (primary, secondary or tertiary), an alkali metal hydroxide, or alkaline earth metal hydroxide, or the like. Illustrative examples of suitable salts include organic salts derived from amino acids, such as glycine and arginine, ammonia, carbonates, bicarbonates, primary, secondary, and tertiary amines, and cyclic amines, such as benzylamines, pyrrolidines, piperidine, morpholine, and piperazine, and inorganic salts derived from sodium, calcium, potassium, magnesium, manganese, iron, copper, zinc, aluminum, and lithium.

The invention also relates to treatment methods employing pharmaceutically acceptable prodrugs of the compounds of Formula (I). The term “prodrug” means a precursor of a designated compound that, following administration to a subject, yields the compound in vivo via a chemical or physiological process such as solvolysis or enzymatic cleavage, or under physiological conditions (e.g., a prodrug on being brought to physiological pH is converted to the compound of Formula (I)). A “pharmaceutically acceptable prodrug” is a prodrug that is not toxic, biologically intolerable, or otherwise biologically unsuitable for administration to the subject. Conventional procedures for the selection and preparation of suitable prodrug derivatives are described, for example, in “Design of Prodrugs”, ed. H. Bundgaard, Elsevier, 1985.

Exemplary prodrugs include compounds having an amino acid residue, or a polypeptide chain of two or more (e.g., two, three or four) amino acid residues, covalently joined through an amide or ester bond to a free amino, hydroxy, or carboxylic acid group of a compound of Formula (I). Examples of amino acid residues include the twenty naturally occurring amino acids, commonly designated by three letter symbols, as well as 4-hydroxyproline, hydroxylysine, demosine, isodemosine, 3-methylhistidine, norvalin, beta-alanine, gamma-aminobutyric acid, citrulline homocysteine, homoserine, ornithine and methionine sulfone.

Additional types of prodrugs may be produced, for instance, by derivatizing free carboxyl groups of structures of Formula (I) as amides or alkyl esters. Exemplary amides include those derived from ammonia, primary C1-6alkyl amines and secondary di(C1-6alkyl) amines. Secondary amines include 5- or 6-membered heterocycloalkyl or heteroaryl ring moieties. Preferred amides are derived from ammonia, C1-3alkyl primary amines, and di(C1-2alkyl)amines. Exemplary esters of the invention include C1-7alkyl, C5-7cycloalkyl, phenyl, and phenyl(C1-6alkyl) esters. Preferred esters include methyl esters. Prodrugs may also be prepared by derivatizing free hydroxy groups using groups including hemisuccinates, phosphate esters, dimethylaminoacetates, and phosphoryloxymethyloxycarbonyls, following procedures such as those outlined in Adv. Drug Delivery Rev. 1996, 19, 115. Carbamate derivatives of hydroxy and amino groups may also yield prodrugs. Carbonate derivatives, sulfonate esters, and sulfate esters of hydroxy groups may also provide prodrugs. Derivatization of hydroxy groups as (acyloxy)methyl and (acyloxy)ethyl ethers, wherein the acyl group may be an alkyl ester, optionally substituted with one or more ether, amine, or carboxylic acid functionalities, or where the acyl group is an amino acid ester as described above, is also useful to yield prodrugs. Prodrugs of this type may be prepared as described in J. Med. Chem. 1996, 39, 10. Free amines can also be derivatized as amides, sulfonamides or phosphonamides. All of these prodrug moieties may incorporate groups including ether, amine, and carboxylic acid functionalities.

The compounds of Formula (I) and their pharmaceutically acceptable salts, pharmaceutically acceptable prodrugs, and pharmaceutically active metabolites (collectively, “agents”) of the present invention are useful as FAAH inhibitors in the methods of the invention. The agents may be used in the inventive methods for the treatment or prevention of medical conditions, diseases, or disorders mediated through inhibition or modulation of FAAH, such as those described herein. Agents according to the invention may therefore be used as an analgesic, neuroprotectant, sedative, appetite stimulant, or contraceptive.

Thus, the pharmaceutical agents may be used to treat subjects diagnosed with or suffering from a disease, disorder, or condition mediated through FAAH activity. The term “treat” or “treating” as used herein is intended to refer to administration of an agent or composition of the invention to a subject for the purpose of effecting a therapeutic or prophylactic benefit through modulation of FAAH activity. Treating includes reversing, ameliorating, alleviating, inhibiting the progress of, lessening the severity of, or preventing a disease, disorder, or condition, or one or more symptoms of such disease, disorder or condition mediated through modulation of FAAH activity. The term “subject” refers to a mammalian patient in need of such treatment, such as a human. “Modulators” include both inhibitors and activators, where “inhibitors” refer to compounds that decrease, prevent, inactivate, desensitize or down-regulate FAAH expression or activity, and “activators” are compounds that increase, activate, facilitate, sensitize, or up-regulate FAAH expression or activity.

Accordingly, the invention relates to methods of using the pharmaceutical agents described herein to treat subjects diagnosed with or suffering from a disease, disorder, or condition mediated through FAAH activity, such as: anxiety, pain, sleep disorders, eating disorders, inflammation, or movement disorders (e.g., multiple sclerosis).

Symptoms or disease states are intended to be included within the scope of “medical conditions, disorders, or diseases.” For example, pain may be associated with various diseases, disorders, or conditions, and may include various etiologies. Illustrative types of pain treatable with a FAAH-modulating agent according to the invention include cancer pain, postoperative pain, GI tract pain, spinal cord injury pain, visceral hyperalgesia, thalamic pain, headache (including stress headache and migraine), low back pain, neck pain, musculoskeletal pain, peripheral neuropathic pain, central neuropathic pain, neurogenerative disorder related pain, and menstrual pain. HIV wasting syndrome includes associated symptoms such as appetite loss and nausea. Parkinson's disease includes, for example, levodopa-induced dyskinesia. Treatment of multiple sclerosis may include treatment of symptoms such as spasticity, neurogenic pain, central pain, or bladder dysfunction. Symptoms of drug withdrawal may be caused by, for example, addiction to opiates or nicotine. Nausea or emesis may be due to chemotherapy, postoperative, or opioid related causes. Treatment of sexual dysfunction may include improving libido or delaying ejaculation. Treatment of cancer may include treatment of glioma. Sleep disorders include, for example, sleep apnea, insomnia, and disorders calling for treatment with an agent having a sedative or narcotic-type effect. Eating disorders include, for example, anorexia or appetite loss associated with a disease such as cancer or HIV infection/AIDS.

In a treatment method according to the invention, an effective amount of a pharmaceutical agent according to the invention is administered to a subject suffering from or diagnosed as having such a disease, disorder, or condition. An “effective amount” means an amount or dose sufficient to generally bring about the desired therapeutic or prophylactic benefit in patients in need of such treatment.

Effective amounts or doses of the agents of the present invention may be ascertained by routine methods such as modeling, dose escalation studies or clinical trials, and by taking into consideration routine factors, e.g., the mode or route of administration or drug delivery, the pharmacokinetics of the agent, the severity and course of the disease, disorder, or condition, the subject's previous or ongoing therapy, the subject's health status and response to drugs, and the judgment of the treating physician. An exemplary dose is in the range of from about 0.001 to about 200 mg of agent per kg of subject's body weight per day, preferably about 0.05 to 100 mg/kg/day, or about 1 to 35 mg/kg/day, in single or divided dosage units (e.g., BID, TID, QID). For a 70-kg human, an illustrative range for a suitable dosage amount is from about 0.05 to about 7 g/day, or about 0.2 to about 2.5 g/day.

Once improvement of the patient's disease, disorder, or condition has occurred, the dose may be adjusted for preventative or maintenance treatment. For example, the dosage or the frequency of administration, or both, may be reduced as a function of the symptoms, to a level at which the desired therapeutic or prophylactic effect is maintained. Of course, if symptoms have been alleviated to an appropriate level, treatment may cease. Patients may, however, require intermittent treatment on a long-term basis upon any recurrence of symptoms.

In addition, the agents of the invention may be used in combination with additional active compounds in the treatment of the above conditions. The additional compounds may be coadministered separately with an agent of Formula (I) or included with such an agent as an additional active ingredient in a pharmaceutical composition according to the invention. In an exemplary embodiment, additional active compounds are those that are known or discovered to be effective in the treatment of conditions, disorders, or diseases mediated by FAAH activity, such as another FAAH modulator or a compound active against another target associated with the particular condition, disorder, or disease. The combination may serve to increase efficacy (e.g., by including in the combination a compound potentiating the potency or effectiveness of an agent according to the invention), decrease one or more side effects, or decrease the required dose of the agent according to the invention. In one illustrative embodiment, a composition according to the invention may contain one or more additional active ingredients selected from opioids, NSAIDs (e.g., ibuprofen, cyclooxygenase-2 (COX-2) inhibitors, and naproxen), gabapentin, pregabalin, tramadol, acetaminophen, and aspirin.

The agents of the invention are used, alone or in combination with one or more other active ingredients, to formulate pharmaceutical compositions of the invention. A pharmaceutical composition of the invention comprises: (a) an effective amount of a pharmaceutical agent in accordance with the invention; and (b) a pharmaceutically acceptable excipient.

A “pharmaceutically acceptable excipient” refers to a substance that is not toxic, biologically intolerable, or otherwise biologically unsuitable for administration to a subject, such as an inert substance, added to a pharmacological composition or otherwise used as a vehicle, carrier, or diluent to facilitate administration of a pharmaceutical agent and that is compatible therewith. Examples of excipients include calcium carbonate, calcium phosphate, various sugars and types of starch, cellulose derivatives, gelatin, vegetable oils, and polyethylene glycols.

Delivery forms of the pharmaceutical compositions containing one or more dosage units of the pharmaceutical agents may be prepared using suitable pharmaceutical excipients and compounding techniques now or later known or available to those skilled in the art. The compositions may be administered in the inventive methods by oral, parenteral, rectal, topical, or ocular routes, or by inhalation.

The preparation may be in the form of tablets, capsules, sachets, dragees, powders, granules, lozenges, powders for reconstitution, liquid preparations, or suppositories. Preferably, the compositions are formulated for intravenous infusion, topical administration, or oral administration.

For oral administration, the compounds of the invention can be provided in the form of tablets or capsules, or as a solution, emulsion, or suspension. To prepare the oral compositions, the agents may be formulated to yield a dosage of, e.g., from about 0.05 to about 50 mg/kg daily, or from about 0.05 to about 20 mg/kg daily, or from about 0.1 to about 10 mg/kg daily.

Oral tablets may include the active ingredient mixed with pharmaceutically acceptable excipients such as inert diluents, disintegrating agents, binding agents, lubricating agents, sweetening agents, flavoring agents, coloring agents and preservative agents. Suitable inert fillers include sodium and calcium carbonate, sodium and calcium phosphate, lactose, starch, sugar, glucose, methyl cellulose, magnesium stearate, mannitol, sorbitol, and the like. Exemplary liquid oral excipients include ethanol, glycerol, water, and the like. Starch, polyvinyl-pyrrolidone (PVP), sodium starch glycolate, microcrystalline cellulose, and alginic acid are suitable disintegrating agents. Binding agents may include starch and gelatin. The lubricating agent, if present, may be magnesium stearate, stearic acid or talc. If desired, the tablets may be coated with a material such as glyceryl monostearate or glyceryl distearate to delay absorption in the gastrointestinal tract, or may be coated with an enteric coating.

Capsules for oral administration include hard and soft gelatin capsules. To prepare hard gelatin capsules, active ingredient may be mixed with a solid, semi-solid, or liquid diluent. Soft gelatin capsules may be prepared by mixing the active ingredient with water, an oil such as peanut oil or olive oil, liquid paraffin, a mixture of mono and di-glycerides of short chain fatty acids, polyethylene glycol 400, or propylene glycol.

Liquids for oral administration may be in the form of suspensions, solutions, emulsions or syrups or may be presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid compositions may optionally contain: pharmaceutically-acceptable excipients such as suspending agents (for example, sorbitol, methyl cellulose, sodium alginate, gelatin, hydroxyethylcellulose, carboxymethylcellulose, aluminum stearate gel and the like); non-aqueous vehicles, e.g., oil (for example, almond oil or fractionated coconut oil), propylene glycol, ethyl alcohol, or water; preservatives (for example, methyl or propyl p-hydroxybenzoate or sorbic acid); wetting agents such as lecithin; and, if desired, flavoring or coloring agents.

The agents of this invention may also be administered by non-oral routes. For example, the compositions may be formulated for rectal administration as a suppository. For parenteral use, including intravenous, intramuscular, intraperitoneal, or subcutaneous routes, the agents of the invention may be provided in sterile aqueous solutions or suspensions, buffered to an appropriate pH and isotonicity or in parenterally acceptable oil. Suitable aqueous vehicles include Ringer's solution and isotonic sodium chloride. Such forms will be presented in unit-dose form such as ampules or disposable injection devices, in multi-dose forms such as vials from which the appropriate dose may be withdrawn, or in a solid form or pre-concentrate that can be used to prepare an injectable formulation. Illustrative infusion doses may range from about 1 to 1000 μg/kg/minute of agent, admixed with a pharmaceutical carrier over a period ranging from several minutes to several days.

For topical administration, the agents may be mixed with a pharmaceutical carrier at a concentration of about 0.1% to about 10% of drug to vehicle. Another mode of administering the agents of the invention may utilize a patch formulation to affect transdermal delivery.

Agents may alternatively be administered in methods of this invention by inhalation, via the nasal or oral routes, e.g., in a spray formulation also containing a suitable carrier.

Chemistry

Exemplary agents useful in methods of the invention will now be described by reference to the illustrative synthetic schemes for their general preparation below and the specific examples that follow. Artisans will recognize that, to obtain the various compounds herein, starting materials may be suitably selected so that the ultimately desired substituents will be carried through the reaction scheme with or without protection as appropriate to yield the desired product. Alternatively, it may desirable to employ, in the place of the ultimately desired substituent, a suitable group that may be carried through the reaction scheme and replaced as appropriate with the desired substituent. Unless otherwise specified, the variables are as defined above in reference to Formula (I). FIGS. 3 and 4 also illustrate these schemes.

Referring to Scheme A, stannanes of formula (III), where P is a suitable hydroxyl protecting group, are prepared as previously described (Boger, J. Med. Chem. 2005, 48, 1849). Stannanes (III) are coupled with various aryl or heteroaryl halides using Stifle coupling procedures. Preferred conditions utilize Pd(PPh3)4 or Pd(P(t-Bu)3)2 as the catalyst. Compounds of formula (IV) are then deprotected (for example, where P is a silyl protecting group, with a silyl deprotecting agent such as TBAF) and oxidized to compounds of Formula (I) using oxidizing agents such as Dess-Martin periodinane or TPAP/NMO.

Referring to Scheme B, compounds of formula (V) may be obtained according to the methods shown in Scheme A. The nitro group may be reduced to an amino group (formula (VI)) using standard nitro reduction methods, such as exposure to SnCl2 or by hydrogenation in the presence of a Pd catalyst. Amines (VI) may be alkylated via alkylation or reductive amination protocols to form amines (VII). Amines (VI) may be alternatively sulfonylated with the appropriately substituted sulfonyl chlorides to form compounds of formula (VIII). Reaction of amines (VI) with suitably substituted acid chlorides or via peptide coupling with appropriate acids (e.g. in the presence of HOAt/EDCI) generate amides (IX). Installation of the Ra substituent may be accomplished before (via alkylation or reductive amination) or after (via alkylation) the sulfonylation/acylation step. One skilled in the art will recognize that Formula (I) includes compounds of formulae (VI), (VII), (VIII), and (IX).

Referring to Scheme C, acetates of formula (X), where R is defined as in Scheme B, may be obtained according to the methods shown in Scheme A. Deprotection of the acetate group, using, for example, a base such as LiOH or NaOMe, gives the corresponding alcohols (XI). These alcohols may in turn be converted to ethers of formula (XII) by treatment with an appropriate alkyl halide in the presence of a base, or with an appropriate alcohol under Mitsunobu conditions (for example, PPh3/DEAD). One skilled in the art will recognize that Formula (I) includes compounds of formulae (XI) and (XII).

Referring to Scheme D, esters of formula (XIII), where R is defined as in Scheme B, and prepared according to Scheme A, may be hydrolyzed to acids (XIV) using a base such as LiOH. Acids (XIV) may be converted to their corresponding amides (XV) by reaction with a suitable amine under peptide coupling conditions (e.g. HOAt/EDCI). One skilled in the art will recognize that Formula (I) includes compounds of formulae (XIII), (XIV), and (XV).

One skilled in the art will recognize that transformations depicted for R1 may analogously be performed for R2.

Referring to Scheme E, pyrimidines (XVI), prepared according to Scheme A, may be converted to uracils (XVII) by treatment of a demethylating agent such as TMSI. One skilled in the art will recognize that Formula (I) includes compounds of formulae (XVI) and (XVII).

The following examples are provided to further illustrate the invention and various preferred embodiments.

Substitution of C2 Side Chain Terminal Phenyl Group. A systematic series of aryl replacements and phenyl substitutions, aryl replacement derivatives (5a-5f), thiophene replacements 5a and 5b, 1-naphthyl substitution 5c, 2-naphthyl derivative 5d proved to be effective inhibitors. Incorporation of the more polar pyridine substitutent 5e and 5f led to reductions in the Ki. FIG. 5 illustrates this series.

Substitution involving the terminal phenyl ring of the alpha acyl side chain provided effective inhibition and the complete range of ortho, meta, or para substituents provided effective FAAH inhibitors (5g-5oo; FIG. 5). However, the carboxylic acid derivatives (5dd-ff) that are deprotonated under the assay conditions did not display strong binding. Typically, hydrophobic or electron-withdrawing substituents enhanced the binding affinity of the inhibitors more significantly than polar or electron-donating substituents. However, and with a couple of notable exceptions, each substituent enhanced binding affinity indicative of additional favorable binding contacts within the active site. Although this may not be surprising for the hydrophobic substituents (CH3, CF3, F, Cl, SCH3≧OCH3, H), it is especially interesting that polar substituents (CO2CH3, NO2, SO2CH3, NH2) can be tolerated in this hydrophobic pocket and that some even enhance inhibitory potency. This appears to be especially true of the m-position where even the methylsulfone 5ll produced an inhibitor of significant potency. whereas the corresponding o- and p-methylsulfone derivatives (5kk and 5mm, respectively) were approximately 10-fold less effective. The potency of such derivatives typically ranged from 5-0.9 nM (Ki), displayed a variable and weak preference for the site of attachment, and the most potent members typically were the m-substituted derivatives. Significantly, 5hh (R═Cl) broke the nanomolar potency barrier providing a Ki of 900 pM. Accordingly, this region provides a rich area where substituents or modifications can be introduced to enhance inhibitor potency, impact features contributing to or improving in vivo properties, and substantially enhance selectivity. The invention, therefore encompasses all hydrophobic as well as hydrophilic and ionic substitution at these positions.

Finally, the alkyne precursors 4 to series 5 inhibitors prepared by the Shonogashira coupling (Method A) were also examined for FAAH inhibition and the results are summarized in FIG. 6. It was observed that there was a loss in activity with the alkynes compared to their corresponding alkane derivatives (FIG. 5) suggesting that this restriction places the terminal aryl ring in a less favorable area in the FAAH active site.

Substitution along the side chain. A systematic series of heteroatoms and electron-withdrawing substituents positioned within the alpha keto side chain was also investigated (FIG. 7). Placing a heteroatom or electron-withdrawing substitutent at the 2-position of the side chain (12a-12d) β to the electrophilic carbonyl resulted in a loss in potency despite their inductive electron-withdrawing character that would be expected to enhance the electrophilic character of the carbonyl. Only the least electronegative atom of the series (X═S, 12b) displayed significant potency and the most electronegative functionality (X═SO2, 12d) resulted in a significant loss in potency. A rough trend in the Ki is observed as heteroatoms move along the chain where heteroatoms at each end of the chain (2- and 6-positions) are better tolerated than in the middle (3-5 positions). At each location, the substitutions exhibited a well-defined trend of CH2≧S>O>NMe>SO>SO2, which reflects the hydrophobic character of this region of FAAH active site. Introduction of a sulfur provided inhibitors that displayed significant potency (12b, 2-position; 12p, 6-position, 12k, 5-position). Other heteroatoms caused reduction in potency as the above delineated trend indicates. At the most tolerant position (position 6), the magnitude of these effects for sulfur, oxygen, and NMe are dampened with each providing effective inhibitors.

A series of amides within the linking chain and hydroxyl substitutions on the chain was also explored (FIG. 8). Amide placement in the side chain led to a loss in inhibitory potency. Consistent with expectations, 13a, but not 13b or 13c, exists as the stable N-acyl hemiaminal and this is reflected in its lower ability to inhibit FAAH. Consistent with the previous series of inhibitors (FIG. 7), a well-defined trend in Ki is observed as the hydroxyl substitution moves along the side chain where the hydroxyl group at each end of the side chain was better tolerated than those in the middle of the side chain. Within this series, only 13f (50%, CDCl3) and 13g (50%, CDCl3) exist in equilibrium with their internal hemiketal. Thus, even though 13f has a lower potency that other compounds of this series, it will prove useful to examine in vivo where the electrophilic carbonyl would potentially be less prone to metabolic reduction due to the reversible hemiketal formation.

Several additional side chain modifications were examined and represent intermediates or byproducts derived from the synthesis of the preceding candidate inhibitors. The results of their examination are summarized in FIG. 9 and highlight several features. Shortening of the side chain and removal of the phenyl group of OL-135 (2b) with a small series of methyl esters (14a-14c) led to a significant progressive decrease in potency. The cyclopropyl and cyclopentyl derivatives 14d and 14e lacking the extended chain and phenyl group similarly resulted in a loss of activity. Interestingly, and in contrast, the simple α-chloroketone 14f was still a submicromolar inhibitor of FAAH although it lacked nearly all of the alpha keto side chain. Presumably this result reflects that inhibitor's increased electrophilic carbonyl reactivity which significantly increases its potency over the known inactive methyl ketone (Boger, D. L.; Miyauchi, H.; et al. J. Med. Chem. 2005, 48, 1849-1856). Placement of a ketone beta to the electrophilic carbonyl (14g) led to a significant loss of inhibitory potency. In this instance, the electrophilic C2 carbonyl of 14g is enolized (>95%, CDCl3) and unreactive toward nucleophilic attack.

Finally two alcohol derivatives were examined, e.g., 14h and 14i, and both resulted in a substantial loss in inhibitory potency with 14h exhibiting a greater loss in activity relative to its corresponding ketone 13d.

Although inhibitory potency among the compounds of the invention varies, other factors such as lack of side effects, selectivity for the FAAH relative to other enzymes, bioavailability, ability to cross biological barriers such as the gut-blood barrier, the blood-cell barrier and the blood-brain barrier, among others, are important for development of an effective pharmaceutical compound. Consequently, lower potency does not mean that an individual compound of Formula I lacks pharmaceutical interest. For example, while pyridine substitution for phenyl on the alpha keto side chain led to lower potency, the selectivity for FAAH was increased as discussed below. Nevertheless, unless otherwise indicated by selectivity or other experimental factors described herein, the compounds of Formula I having higher inhibitory Ki's are preferred according to the invention.

Summarized in FIG. 11 are the results of the selectivity screening of selected candidate inhibitors. In general, the inhibitors were very selective for FAAH over TGH and KIAA1361. The pyridyl replacements (5e, 5f) of the terminal phenyl group of the alpha keto side chain proved very selective for FAAH over KIAA1363, but only moderately selective for FAAH over TGH. Substitution on the terminal phenyl ring of 2b also provided selective inhibitors and this was relatively independent of the substitution position (o-, m-, or p-) and whether it was electron-donating or electron-withdrawing (5j-5l vs. 5gg-5ii).

The following experimental description of individual compounds of Formula I further illustrates the present invention. These examples and their corresponding biological activities provide further information about the present invention. However, the invention is fully characterized in the foregoing Summary and the following claims. The examples are not meant to act as limitations of the invention. Additional embodiments and examples will be readily apparent to the practitioner based upon the foregoing Summary, synthetic schemes and the examples provided below.

General Procedure A. A solution of the aldehyde (1 equiv) and BrPh3P(CH2)5CO2H (S1, 1.05 equiv) in anhydrous THF (20 mL/4.46 mmol of aldehyde) at −78° C. was treated with a suspension of t-BuOK (1.4 equiv) in anhydrous THF (8 mL). The reaction mixture was allowed to warm at 0° C. and was stirred for 20 h. The reaction mixture was concentrated, diluted with aqueous 4 N NaOH and extracted with EtOAc. The aqueous phase was treated with aqueous 4 N HCl and extracted with EtOAc. The organic layer was dried over Na2SO4, filtered and concentrated. Flash chromatography (SiO2) afforded the corresponding unsaturated acid. The mixture of isomers (1 equiv) in EtOAc (10 mL) was treated with 10% Pd/C (0.2 equiv) and purged with H2. After stirring for 24 h at 25° C., the reaction mixture was filtered through Celite and concentrated to afford the product.

General Procedure B. A solution of 5-(2-pyridyl)oxazole (1.0 equiv) in anhydrous THF (3 mL/0.34 mmol) at −78° C. was treated dropwise with a solution of n-BuLi in hexanes (2.5 M, 1.2 equiv) under N2 and the resulting solution was stirred at −78° C. for 35 min. A solution of ZnCl2 in THF (0.5 M, 2 equiv) was added to the mixture and the mixture was allowed to warm to 0° C. After stirring at 0° C. for 45 min, CuI (1.2 equiv) was added to the mixture. After the mixture was stirred at 0° C. for 15 min, a solution of the acid chloride (1.2 equiv; prepared from the corresponding carboxylic acid and oxalyl chloride) in anhydrous THF (2 mL) was added dropwise, and the mixture was stirred for an additional 1 h. The reaction mixture was quenched with addition of saturated aqueous NaHCO3 and extracted with EtOAc. The organic layer was filtered through Celite, dried over anhydrous Na2SO4, filtered and evaporated to yield the crude product, which was purified by flash chromatography (SiO2).

General Procedure C. A solution of 5-(2-pyridyl)oxazole (1.0 equiv) in anhydrous THF (5.0 mL/0.51 mmol) at −78° C. was treated dropwise with a solution of n-BuLi in hexanes (2.5 M, 1.1 equiv) under N2 and the resulting solution was stirred at −78° C. for 20 min. A solution of ZnCl2 in THF (0.5 M, 2.0 equiv) was added to the mixture, and the mixture was warmed to 0° C. After stirring at 0° C. for 45 min, CuI (1.0 equiv) was added to the mixture. After the mixture was stirred at 0° C. for 10 min, a solution of the acid chloride (1.2 equiv; prepared from the corresponding carboxylic acid and oxalyl chloride) in anhydrous THF (3.0 mL) was added dropwise, and the mixture was stirred at 0° C. for an additional 1 h. The reaction mixture was diluted with a 1:1 mixture of hexanes and EtOAc (60 mL) and washed with 15% aqueous NH4OH (2×30 mL), water (30 mL) and saturated aqueous NaCl (30 mL). The organic layer was dried over anhydrous Na2SO4, filtered, and evaporated. Column chromatography (SiO2) afforded the product.

General Procedure D. A solution of the alkyne (1.0 equiv) in anhydrous THF (0.5 mL/0.12 mmol of alkyne) was treated with the aryl iodide (1.5 equiv), Ag2CO3 (0.7 equiv), Bu4NCl (1.8 equiv) and PdCl2(PPh3)2 (0.10 equiv). After stirring for 22 h at 90° C., the reaction was quenched with aqueous saturated NaCl and extracted with EtOAc. The organic layer was dried over Na2SO4, filtered and concentrated. Chromatography (SiO2) afforded the product.

General Procedure F. A solution of the alkyne (1 equiv) in EtOAc (0.5 mL/0.027 mmol of alkyne) was treated with 10% Pd/C (0.2 equiv). The reaction mixture was purged with H2 and stirred overnight at 25° C. The suspension was filtered through Celite and concentrated.

General Procedure G. A solution of the alkyne (1 equiv) in anhydrous THF (1 mL/0.038 mmol of alkyne) was treated with a catalytic amount of Raney nickel (washed before use with THF). The reaction mixture was purged with H2 and stirred at 25° C. overnight. The suspension was filtered through Celite and concentrated. The crude product was dissolved with anhydrous CH2Cl2 (2 mL) and treated with Dess-Martin reagent (1.5 equiv). After stirring for 3 h at 25° C., the reaction mixture was quenched with saturated aqueous Na2CO3 and saturated aqueous Na2S2O3. After stirring for 15 min, the mixture was extracted with CH2Cl2. The organic layer was dried over Na2SO4, filtered and concentrated. Chromatography (SiO2) afforded the product.

General Procedure H. A solution of the sulfide (1.0 equiv) in anhydrous CH2Cl2 (0.7 mL/0.050 mmol of sulfide) at 0° C. was treated with m-CPBA (2.2 equiv). After 1 h, the reaction mixture was quenched with saturated aqueous NaHCO3 and extracted with CH2Cl2. The organic layer was dried on Na2SO4, filtered and concentrated. Chromatography (SiO2) afforded the product.

General Procedure I. A solution of the alkyne (1 equiv) in a mixture of THF/MeOH (1 mL, 1/1; for 0.12 mmol of alkyne) was treated with 10% Pd/C (0.2 equiv). The suspension was purged under H2 and stirred for 20 h at 25° C. 10% Pd/C (0.2 equiv) was added again and the reaction mixture was stirred for an additional 20 h at 25° C. Chromatography (SiO2) afforded the product.

General Procedure J. A solution of the carbamate (1 equiv) in CH2Cl2 (0.2 mL/0.045 mmol of carbamate) at 0° C. was treated with 0.2 mL of TFA. After stirring for 1 h at 0° C., the reaction mixture was concentrated, diluted with aqueous saturated NaHCO3 and extracted with CH2Cl2. The organic layer was dried over Na2SO4, filtered and concentrated. Chromatography (SiO2) afforded the product.

General Procedure K. A solution of the acid (1 equiv; prepared by hydrogenation of the 4-hydroxycinnamic acid) in anhydrous DMF (16 mL/4.2 mmol of acid) at 0° C. was treated with Bu4NI (0.01 equiv) and a suspension of NaH (60% in mineral oil, 2.7 equiv) in anhydrous DMF (10 mL). After stirring for 10 min, benzyl bromide (1.3 equiv) was added dropwise. The reaction mixture was allowed to warm at 25° C. and was stirred overnight. The reaction was quenched with aqueous 10% HCl and extracted with EtOAc. The organic layer was washed with saturated aqueous NH4Cl, dried and concentrated. Column chromatography (SiO2) afforded the product.

General Procedure L. The methyl ester (1 equiv) was dissolved in THF (0.15 mL/0.033 mmol) and LiOH (1.1 equiv) was added. The reaction mixture was stirred at room temperature overnight, diluted with H2O and acidified to pH 2 with aqueous 1 N HCl. The acidic aqueous phase was extracted with EtOAc and the organic extracts were combined, dried over anhydrous Na2SO4 and concentrated. Preparative thin layer chromatography (SiO2) afforded the pure acids.

General Procedure M. A solution of the sulfide (1 equiv) in anhydrous CH2Cl2 (0.1 M) was cooled to 0° C. and treated with m-CPBA (1.0 or 1.5 equiv). The suspension was stirred for 2 h and quenched with saturated aqueous NaHCO3. The organic layer was dried over anhydrous Na2SO4, filtered and concentrated. PTLC (66% EtOAc-hexanes, SiO2) afforded in the order of elution the sulfones and the sulfoxides in good combined yields.

General Procedure N. The methyl ester (1.0 equiv) was dissolved in 1:1 THF:H2O (4 mL/0.62 mmol of methyl ester) and LiOH (1.0 equiv) was added. After stirring at room temperature for 6 h, the reaction mixture was concentrated and the residue dried under high vacuum. The dried lithium carboxylate salt was dissolved in anhydrous DMF (5 mL) and HATU (1.0 equiv) was added. The reaction mixture was stirred for 10 min before adding a solution containing the requisite amine (1.1 equiv) and i-Pr2NEt (2.1 equiv) in anhydrous DMF (2 mL). After stirring at room temperature for 1 h, the DMF was removed in vacuo and the residue taken up into EtOAc. The organic layer was washed successively with aqueous 0.1 N HCl, 0.1 N NaOH and H2O, and then dried over anhydrous Na2SO4 and concentrated. The crude amides were purified using PTLC (SiO2).

General Procedure O. The TIPS ether (1 equiv) was dissolved in anhydrous THF (0.5 mL/0.12 mmol of TIPS ether) under Ar and cooled to 0° C. Bu4NF (1.0 M solution in THF, 1.3 equiv) was added dropwise and the reaction mixture stirred for 30 min. The ice bath was removed and the reaction mixture was allowed to stir for 3 h at room temperature. The THF was removed under a stream of N2 and the residue taken up into Et2O and washed with water. The organic phase was dried over anhydrous Na2SO4 and concentrated. PTLC (SiO2) afforded the alcohol.

General Procedure P. A solution of the alcohol (1 equiv) in anhydrous CH2Cl2 (0.2 M) at 0° C. was treated with PCC (1.5 equiv) and the mixture was stirred for 45 min. The reaction mixture was allowed to warm at 25° C. and stirred for 3 h. The suspension was filtered through Celite and concentrated. Column chromatography (SiO2) afforded the aldehyde.

General Procedure Q. A solution of the aldehyde (1 equiv) in anhydrous THF (65 mL/20.0 mmol of aldehyde) at 0° C. was treated with the Grignard reagent (1.2 equiv). After stirring for 30 min, the reaction mixture was quenched with saturated aqueous NH4Cl. The organic layer was extracted with EtOAc, dried over Na2SO4, filtered and concentrated. Column chromatography (EtOAc-hexanes) afforded the alcohol. A solution of the alcohol (1 equiv) in anhydrous THF at 0° C. was treated with NaH (1.2 equiv). After 15 min, TIPS-OTf (1.2 equiv) was added dropwise and the reaction mixture was allowed to warm to 25° C. After 1 h, the reaction was quenched with saturated aqueous NH4Cl. The organic phase was extracted with EtOAc, dried over Na2SO4, filtered and concentrated. Column chromatography (SiO2) afforded the TIPS protected alcohol.

General Procedure R. A solution of the benzyl protected alcohol (1 equiv) in EtOAc (0.22 M) was treated with 10% Pd/C (0.2 equiv). The reaction mixture was purged with H2 and stirred overnight at 25° C. The suspension was filtered through Celite, concentrated and purified by column chromatography (SiO2) to afford the alcohol.

General Procedure S. A solution of the alcohol (1 equiv) in anhydrous DMF (0.14 M) was treated with PDC (3 equiv). After stirring at 25° C. for 20 h, the reaction mixture was quenched with saturated aqueous NH4Cl. The organic layer was extracted with CH2Cl2, dried over Na2SO4, filtered and concentrated. Column chromatography (SiO2) afforded the carboxylic acid.